use strict;
use warnings;
my $string;
while (1){
print "Please enter 1-5 letters: ";
chomp ($string = <STDIN>);
last if $string =~ m/^[a-z]{1,5}$/i;
# last if $string =~ m/^\w{1,5}$/;
print "that is wrong....try again: ";
}
I think the problem was not the pattern so much as the rest of the
logic.
The pattern you have will match a lower- or upper-case letter of the
alphabet one or five times. I can't see how anchoring it to the start or
end of the $string would help anything other than perhaps internal
efficiency, for which I'd anchor it at both ends (^ and $ for start and
end). I would suggest using the /i modifier, so instead of /[a-zA-Z]/ to
match any letter, you could /[a-z]/i.
But that's not really 'any letter' -- it's just a to z, which may ignore
accented and other UTF-8 characters. You can find better options in
perldoc perlre -- see esp. the POSIX section.
Your original code also seemed to be warning of an error before taking
input, but I guess that's a cut-n-paste issue.
Hth
lee
> From: M K Scott [mailto:[EMAIL PROTECTED]
>
> I have tried that to no avail. I have also tried a simple
> match of !~ m/(m|f){1}/ and even put in the code you
> suggested to read !~ m/^(m|f){1}$/ but this still doesn't
> work properly. Input of "d" or "T" will work to say it is
> incorrect and input of "m" or "f" will be accepted but I was
> under the impression that the {1} would limit it to only
> accept a single character while in practice it still accepts
> "ff" and "mmm". Any ideas?
>
> One further question though, an example question I am doing
> asks for a text file to be read in and the number of digits
> to be counted (ie 3 "1"'s, 6 "2"'s etc) and I can read input
> in and do a 'getc' and pattern match that against a hash
> containing word references to the numbers and then add one to
> a count but is this the best way to do this?
>
> Thanks again,
> Mark
>
> ________________________________
>
> From: John W. Krahn [mailto:[EMAIL PROTECTED]
> Sent: Wed 20/09/2006 01:12
> To: Perl Beginners
> Subject: Re: Newbie Question
>
>
>
> M K Scott wrote:
> > Hi all,
>
> Hello,
>
> > Please forgive the newbie nature of this question but i'm just
> > starting off teaching myself perl from scratch and so need a little
> > clarification.
> >
> > I am trying to put together a script to do pattern matching
> and while
> > I can get the basic syntax alright it doesn't seem to be working as
> > expected. For one example I need to match a user input
> and make sure
> > it is a certain length (i.e. doesn't exceed a certain number of
> > characters) and this is the code so far:
> >
> > while ($string != m/[a-zA-Z]{1,5}/ )
> > { print("that is wrong....try again: ");
> > chomp ($string = <STDIN>); }
>
> You need to anchor the pattern like /^[a-zA-Z]{1,5}$/
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